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Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Two (E,E)- and (Z,E)-thiazol-5-ylpenta-2,4-dienones
Leonid Breydo1, Charles L Barnes, Kent S Gates
1Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211, USA.
Abstract:
In order to characterize the structural elements that might play a role in non-covalent DNA binding by the antitumor antibiotic leinamycin, we have solved the crystal structures of the two leinamycin analogs, methyl (R)-5-[2-[1-(tert-butoxycarbonylamino)ethyl]thiazol-4-yl]penta-(E,E)-2,4-dienoate, C(16)H(22)N(2)O(4)S, (II), and 2-methyl-8-oxa-16-thia-3,17-diazabicyclo[12.2.1]heptadeca-(Z,E)-1(17),10,12,14-tetraene-4,9-dione, C(14)H(16)N(2)O(3)S, (III). The penta-2,4-dienone moiety in both of these analogs adopts a conformation close to planarity, with the thiazole ring twisted out of the plane by 12.9 (2) degrees in (II) and by 21.4 (4) degrees in (III).
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